Soft sample scaling in a turbo decoder
US7340013B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2002 |
| Grant date | Mar 4, 2008 |
| Priority date | — |
| Expiry date | Dec 25, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/067
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A receiver for iterative decoding of a received, encoded signal employs slot-based scaling of soft samples. Iterative decoding employs a constituent maximum a priori (MAP) decoder for each constituent encoding of information of the encoded signal. Root mean square (RMS) values for soft samples over a slot are selected for dynamic range scaling. Squared RMS values are combined and equal the squared RMS value for a frame multiplied by a control constant, and this relationship may be employed to derive scaling constants for each slot. Alternatively, the square root of the RMS value multiplied by a constant serves as an SNR estimator that may be employed to scale samples to reduce dynamic range and modify logarithmic correction values for max* term calculation during log-MAP decoding.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.